Device and method for storing thermal energy

Abstract

A device to store energy includes a phase change material (PCM), with a phase change temperature Tc, contained in a sealed container and constituting a storage core. A source to exchange heat with the PCM, at a temperature TA, to cause a phase change of the PCM. A recuperator to exchange heat with the PCM, at a temperature TB, to cause a phase change of the PCM in the opposite direction to the phase change produced by the source. A controller to control the heat flows between the PCM, the source and the recuperator. An apertured support in contact with the PCM in the sealed container and in thermal contact with the source and the recuperator.

Description

RELATED APPLICATIONS[0001]This application is a §371 application from PCT / EP2015 / 066950 filed Jul. 23, 2015, which claims priority from French Patent Application No. 14 57129 filed Jul. 23, 2014 and French Patent Application No. 15 51741 filed Mar. 02, 2015, each of which is incorporated herein by reference in its entirety.FIELD OF THE INVENTION[0002]The invention relates to a device and a method for storing thermal energy. The invention is more particularly, but not exclusively, intended for an climatic apparatus or for a facility that uses apparatuses for controlling the climatic environment in a premises. The terms “climatic apparatus” denote any device for heating, air conditioning, mechanical ventilation or production of water at controlled temperature.BACKGROUND OF THE INVENTION[0003]Such climatic apparatuses consume energy, generally of electrical origin, which electrical energy is used directly to produce heat, for example by the passage thereof through an electric resistanc...

AI Technical Summary

Benefits of technology

The patent describes a support system that helps to keep a phase change material (PCM) at a uniform temperature, without causing the PCM to become too cool or too hot. This support system also helps to store energy when it’s being consumed, and to reduce or stop energy consumption when it’s not being used.

Problems solved by technology

The energy demand emanating from climatic apparatuses is not uniform throughout the day, week or year.

This lack of uniformity of the consumption is particularly tricky to manage when the energy consumption is electric and when it cannot be stored as such.

The situation is more particularly tricky when the energy production uses uncontrolled intermittent production means, such as wind or solar means.

Both the peak periods and off-peak periods pose a problem.

However, this thermodynamic principle encounters practical difficulties.

A first difficulty is linked to obtaining a uniform temperature in the body that is the subject of the phase transition.

Indeed, the phase change materials (PCM) are not by themselves good heat conductors.

Thus, when the heat transfer fluid intended to extract the latent heat therefrom, for example air, sweeps over the surface of the block, the thermal resistance that accumulates between the external exchange surface and the state change front rapidly becomes predominant and limits the thermal power.

Besides the cost of these materials, this method from the prior art also has implementation drawbacks.

Thus, the solution from the prior art that consists in separating, by encapsulation, the PCM into small amounts is disadvantageous from the point of view of supercooling.

Images